no_expansion

Don’t allow expansion of the search pattern

Specification

  • Alias: None

  • Arguments: None

  • Default: algorithm may expand pattern size

Description

In general, pattern search methods can expand and contract their step lengths. SCOLIB pattern search methods contract the step length by the value contraction_factor, and they expand the step length by the value (1/contraction_factor). The expand_after_success control specifies how many successful objective function improvements must occur with a specific step length prior to expansion of the step length, whereas the no_expansion flag instructs the algorithm to forgo pattern expansion altogether.